Work rest fob



A. J. KOON 1,790,669

WORK REST FOR BAR AND TUBE GRINDING MACHINES Feb. 3, 1931.

Filed June 25, 1928 2 Sheets-Sheet 1-- Feb. -3, 1931. KOQN 1,790,669

WORK REST FOR BAR AND TUBE GRINDING MACHINES Filed June 25, 1928 2 Sheets-Sheet 2 Patented Feb. 3, 1931 UNHTD stars ARTHUR J. KOON, OF GRAND vRAIEIIDS, MICHIGAN WORK REST FOR BAR AND TUBE GRINDING MACHINES Application filed June 25, 1928. Serial No. 288,011.

This invention relates to the art of bar and tube grinders, and has reference more particularly to an improved work rest for support ing the rotating bar or tube on either side of the grinding wheel.

The primary object of the present invention is to provide an improved work support or steady rest that will hold and maintain in accurate alinement a round bar or tube while either a turning tool or a grinding wheel is finishing the surface of the same so as to cause the turning tool or grinding wheel to produce a true cylindrical shape while the bar or tube is passing through the steady rests. Another object of the invention is to provide a work-supporting structure that will effectively oppose the thrust of the turning tool or grinding wheel on the work diametrically opposite the point of contact of the latter with the work so as to prevent the bar or tube from springing away from the tool, and insure a uniform diameter of the finished work. A still further object is to provide an improved manner and means of mounting the work-supporting rollers or other work-supporting members permitting the latter to be easily adjusted toward and from each other to accommodate bars and tubes of varying diameters and also to be adjusted angularly to the same helix or feed angle of the bar or tube while the latter is passing the grinding or turning tool. A still further object is to provide an improved form of work-supporting rollers which will present a line contact to the work, instead of a mere point contact,

thereby avoiding a crushing contact, which is a very desirable feature when finishing thin wall tubing of 20 or less gage wall thickness.

Still other objects and advantages of the invention will be apparent to persons skilled in the art as the same becomes better understood by reference to the following detailed description, taken in connection with the accompanying drawings in which I have illustrated a practical and approved embodiment of the principle of the invention, and where- 1n Fig. 1 is a side elevation, with the position o t e grindi g wheel indicated.v by dotted 59 lines;

i Fig. 2 is a vertical section on the line 2--2 of Fig. 1

Fig. 3 is a horizontal section taken on the line 33 of Fig. 1';

Fig. 4: is a sectional detail illustrating an angle position of one of the rollers to the work;

Fig. 5 is a diagram illustrating the posi tions of contact of the three rollers with the work.

Referring to the drawings, 10 designates as an entirety a vertical C-frame on which the roller carriers, rollers and their adjusting devices are mounted. The structural details of the lower (vertical) and intermediate, (horizontal) roller-carrying and adjusting devices are identical and will, therefore, be identified by the same reference characters, and a description of one will suffice for both. Cast or otherwise formed on-or in the frame 10 is a cradle 11 F ig. 3) which, in cooperation with a pair of gibs 12 secured to the upper longitudinal edges of the cradle by screws 13, constitutes a slideway for the flat base 14 of a longitudinally split cylinder 15 that constitutes a slide and clamp for the cylindrical stem 16 of a roller carrier. The split side of the cylinder 15 is formed with apertured lugs 17, through opposedpairs of which is passed a clamp screw 18 that screws into a sleeve nut 19 fitted into the aperture of one of the lugs 17 and locked against turning by a key 20. The screw 18 is formed with a squared head 18 adapted to receive a wrench for securely clamping the stem 16 of the roller carrier in any angularly adjusted position.

The cylindrical shank 16 of the roller carrier is formed at its inner end with a head 21,

on the face of which are seated a pair of opformed with a central groove 21 and the bottoms of the journal boxes 22 are formed with tongues 22 fitting said grooves. The journal boxes 22 are secured to the carrier head 21 by screws 26 entered from the outer sides of the head 21 into the outer sides of the journal boxes. A gage for indicating the angular set of the roller may consist of graduated scale division marks 27 on the inner end of the roller carrier clamp cooperating with a pointer 28 on the stem 16 of the roller carrier.

On the under side of the clamp slide 15 is an integral lug 29 formed with athreaded aperture 29' to receive a lead screw 30 that is rotatably mounted at 31 in an end wall of the cradle 11 and is confined against endwise movement by collars 32 and 33 thereon. The outer end of the lead screw 30 has a squared e head 30 for the application of a wrench to effect adjustment of the roller carrier and roller toward and from the work, as required by the diameter of the latter.

The carrying and adjusting means for the upper roller 25 are to some extent similar to those of the lower and intermediate rollers 25, but slightly modified to maintain the engagement of the roller 25 with the work under yielding spring pressure. As shown at the top of Fig. 1, a longitudinally split cyhn der 34 has its base .34 adjustably secured on the frame 10 by clamps 35 and clamp screws 35, and in the cylinder 34 is mounted a sleeve bushing 36 adapted to be tightly clamped n the cylinder by the clamp screws 18. Slidable endwise within the bushing sleeve 1s a cylindrical stem 16, the'head 21 of which has mounted thereon. the journal boxes 22 for the upper roller 25', the journal box construction and roller mounting being identical with those previously described. The sleeve bushing 36 is formed with an internal longitudinal spline or feather 36' engaged with a longitudinal groove 16 in the roller carrier stem 16' so as to lock the latter against rotation while permitting it to slide freely endwise when the bushing 36 is clamped against rotation. In the stem 16 is an axial recess or socket 37 forming a chamber for a spiral thrust'spring 38 the lower end of which foots on the bottom of the socket. Extending through the spring 38 is a movement-limiting rod 39 threaded into the stem 16 below the recess'37 and at its upper end extending through an opening 40 in acap piece'41 that covers the upper end of the bushing 36 and is secured to the cylinder .34 by cap screws 42 (Fig. 1). The upper end of the rod 39 is threaded to receive an adjusting nut 43 and lock nut 44. From the foregoing it will be seen that by loosening the clamp screws 18 all of the roller carriers can be angularly adj usted about their longitudinal axes whereby to set the rollers 25, 25 at an angle to the axis of the work corresponding to the helix or feed angle of the latter, and again tightened to maintain the rollers in set position. By manipulating the lead screws 30, the lower and intermediate roller carriers can be bodily adjusted as required by the diameter of the work; and by manipulating the adjusting nut 43, the pressure roller 25 can be correspondingly set according to the diameter of the work. If greater ustment than that afforded bythe nut 43 is required, the clamp screws 35 can be loosened, and the cylinder 34 adjusted upwardly and again clamped in its new position. The adjusting nut 43 will normally be out of contact with the top of the cap 41 when the roller 25 is engaged with the work, so as to make the thrust of the spring 38 effective on the roller 25.

By reference to Figs. 1 and 5 it will be 0] served that the roller 25 of the horizontal roller carrier engages the work at a point diametrically opposite to the point of contact of the grinding wheel (indicated at G in Fig. 1), and the top roller 25 and the bottom roller 25 engage the work at points on the opposite side of a vertical plane in which the axis of the worklies from that on which the point of contact of the other roller 25 lies; or, in other words, the points of contact of roller 25 and the lower roller 25 are more than 90 from the point of contact of the intermediate roller 25. The work is thus so held that it cannot accidentally squeeze out from between the top and bottom rollers, and the spring thrust of the top roller 25' always maintains the work in contact with the rollers 25. The described relation of the three points of contact with the work remains the same between the minimum and maximum limits of work diameters. within capacity of the device. This insures the holding of the work in 1 xed position during its feed past the grinding wheel and prevents any springing away from the latter and also efi cctively resists vertical-vibrations of the work which the grinding wheel tends to set up, so that all high spots and excess sur face material are removed by the turning tool or grinding wheel, and, since the horizontal distance between the contact points of the grinding wheel and the diametrically opposed roller always remains fixed, as determined by the operator, and vertical vibrations of the work are effectively resisted, a uniform diameter of the finished work is insured.

The drawings and foregoing description set forth a desirable and G'ffiClGIlt embodiment of the principle of the invention, but manifestly changes and modifications in the structural details may be resorted to without departing from the principle of the invention or sacrificing any of the advantages thereof. Hence, I do not limit the invention to the precise embodiment shown but reserve such Variations, modifications and mechanical equivalents as fall within the spirit and purview of the claims.

I claim 1. In a work rest of the character described, the combination of an upright frame, a pair of opposed carriers swiveled on said frame in axial alinement with each other, a third carrier swiveled on said frame on an axis at right angles to the axes of said pair of carriers, work-engaging members mounted on the inner ends of said carriers, and means for clamping said carriers with their work-engaging members set at any predeten mined angle to the axis of the work passing between them.

2. In a work rest of the character described, the combination of an upright frame, a pair of opposed roller carriers swiveled on said frame in axial alinement with each other, a third roller carrier swiveled on said frame on an axis at right angles to the axes of said pair of roller carriers, work-engaging rollers ournaled on the inner ends of said carriers, said rollers being so disposed that the points of contact with the work of the rollers on said axially alined carriers are spaced more than ninety degrees from the point of contact with the work of the roller on said third roller carrier, and means for clamping said carriers with their rollers set at any predetermined angle to the axis of the work passing between them.

3. In a work rest of the character described, the combination of an upright frame, three angularly disposed carriers swiveled on said frame, work-engaging members nonyieldingly mounted on the inner ends of two of said carriers, self-locking means for adjusting said two carriers toward and from the work, a spring constantly urging the other carrier toward the work, and means for locking said carriers against turning with their work-engaging members set at any predetermined angle to the axis of the work.

4:. In a work rest of the character described, the combination of an upright frame, a pair of opposed roller carriers swiveled on said frame in axial alinement with each other, a third roller carrier swiveled on said frame on an axis at right angles to the axes of said pair of roller carriers, work-engaging rollers journaled on the inner ends of said carriers, self-locking means for adjusting two of said carriers toward and from the work, a spring constantly urging the other carrier toward the work, and means for locking said carriers against turning with their rollers set at any predetermined angle to the axis of the work.

5. In a work rest of the character described, the combination of an upright frame, a pair of opposed roller carriers swiveled on said frame in axial alinement with each other, a third roller carrier swiveled on said frame on an axis at right angles to the axes of said pair of roller carriers, work-engaging rollers journaled on the inner ends of said carriers, said rollers being so disposed that the points of contact with the work of the rollers on said axially alined carriers are spaced more than ninety degrees from the point of contact with the work of the roller on said third roller carrier, self-locking means for adjusting one of said opposed carriers and said third carrier toward and from the work, a spring constantly urging the other of said opposed carriers toward the work, and means for locking said carriers against turning with their rollers set at any predetermined angle to the axis of the work.

6. In a work rest of the character described, the combination of an upright frame, a pair of slides mounted on said frame at right angles to each other, roller carriers swiveled in said slides, work-engaging rollers journaled on the inner ends of said carriers, lead screws journaled in said frame engaged with said slides for adjusting said rollers toward and from the work, a third roller carrier swiveled in said frame in axial alinement with one of said first-named roller carriers, a work-engaging roller journaled on the inner end of said last-named carrier, a spring urging said last-named roller carrier toward the work, and means for locking said carriers against turning with their rollers set at any predetermined angle to the axis of the work.

7. In a work rest of the character described, the combination of an upright frame, a group of angularly disposed roller carriers swiveled on said frame, work-engaging rollers journaled on the inner ends of said carriers, said rollers being formed with transversely concave peripheries, and means for locking said carriers against turning with their rollers set at any predetermined angle to the work passing between them.

8. In a work rest of the character described, the combination of an upright frame, three angularly disposed roller carriers swiveled on said frame, work-engaging rollers journaled on the inner ends of said carriers, said rollers being formed with transversely concave peripheries, means for adjusting two of said carriers toward and from the work, a spring urging the other carrier toward the work, and means for locking said carriers against turning with their rollers set at any predetermined angle to the work passing between them.

ARTHUR J. noon. 

